a) Ca(OH)2(aq)+ Ca(HCO3)2(aq) $\rightarrow$ 2CaCO3(s) + 2H2O(l)
b) Moles = $\frac{volume\times Molarity}{1000}$, Moles of Ca2+ = $\frac{90 \times 0.01 }{1000}$ = 0.0009 moles
c) Water will still be hard since not all calcium ions will have been precipitated when soap is added it initial;y forms scam then later produces lather
johnmulu answered the question on February 10, 2017 at 13:40
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